An unseen interview with the late Apple co-founder Steve Jobs has emerged online. Filmed in 1994, a 39-year old Jobs predicts that his work will be obsolete by the time he reaches 50, Digital Spy said.

The interview was shot while Jobs was working at NeXT, which he founded following his departure from Apple in 1985.

"All the work that I have done in my life will be obsolete by the time I am 50," Jobs said at the time.

He explained how past technology contributes to future innovations, but is quickly forgotten. "It's sort of like sediment of rocks. You're building up a mountain and you get to contribute your little layer of sedimentary rock to make the mountain that much higher.

"But no-one on the surface, unless they have X-ray vision, will see your sediment. They'll stand on it. It'll be appreciated by that rare geologist," he said. Jobs added: "This is a field where one does not write a principia, which holds up for two hundred years.

"This is not a field where one paints a painting that will be looked at for centuries, or builds a church that will be admired and looked at in astonishment for centuries. No.

"This is a field where one does one's work and in ten years it's obsolete, and really will not be usable within ten or 20 years."

Two years after the interview was shot, Jobs returned to Apple where he worked his way to the eventual CEO position until his death on October 5, 2011.

The excerpt is from the hour-long documentary Steve Jobs: Visionary Entrepreneur, which is available to buy from the Silicon Valley Historical Association.